Show rulers and create drawing guides
Let's start by looking at our rulers.
Rulers are great for measuring and placing objects accurately.
We can show or hide rulers at any time by going to View, Rulers, Show Rulers.
And if you want to change the measurement units, head over to Preferences, Units, and pick what works best for you.
The best part is Illustrator actually gives you two types of rulers global rulers, which sit at the top and left of your whole document, and then artboard rulers which sit at the top left of whichever artboard you're working on.
What's the big difference?
With artboard rulers, the origin point resets at each artboard, while global rulers allow you to set the measurement origin to anywhere in the document.
We can change or switch between these settings by going to View, Rulers, Change to Artboard Rulers.
One of the best parts of using rulers in your workflow is that you can create guides directly from them.
Just click and drag down or across from your ruler to pull out a guide.
Guides can appear in lines or dots, and you can even customize their color in Preferences, Guides & Grid.
By default, guides are unlocked so you can move them freely, but if you want them fixed in place, go to View, Guides, Lock Guides.
You can show or hide guides at any time under View, Guides, Show/Hide.
And if you want to start fresh, just select View, Guides, Clear Guides.